Portable engine



FIG. 1 is a front view of a portable engine embodying my new design;

FIG. 2 is a top view of the design illustrated in FIG. 1;

FIG. 3 is a side view of the design illustrated in FIG. 1;

FIG. 4 is an opposite side view of the design illustrated in FIG. 1;and,

FIG. 5 is a bottom view of the design illustrated in FIG. 1.

The broken line showing of the environment is for illustrative purposesonly and forms no part of the claimed design.

The rear view is not part of the claimed design.

The ornamental design for a portable engine, as shown and described.